Develop Reference

how to get data from mysql database into recycler view?

I am making an app that let users create meetings and I would like the details of the meeting (eg name, type, location) in a recycler view.I ran the php code by itself and was able to get the values from the database.
Currently, I am getting an error of
java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference
at in recyclerviewAdapter
holder.Name.setText(users.getName());
holder.Type.setText(users.getType());
holder.Location.setText(users.getLocation());
which is linked to
public class Users {
private String name,type,location;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getType() {
return type;
}
public void setType(String type) {
this.type = type;
}
public String getLocation() {
return location;
}
public void setLocation(String location) {
this.location = location;
}
}
recyclerviewAdapter
public class UserAdapter extends RecyclerView.Adapter<UserAdapter.UserHolder>{
Context context;
List<Users> usersList;
public UserAdapter(Context context, List<Users> usersList) {
this.context = context;
this.usersList = usersList;
}
#NonNull
#Override
public UserHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View userLayout= LayoutInflater.from(parent.getContext()).inflate(R.layout.activity_main2,parent,false);
return new UserHolder(userLayout);
}
#Override
public void onBindViewHolder(#NonNull UserHolder holder, int position) {
Users users=usersList.get(position);
holder.Name.setText(users.getName());
holder.Type.setText(users.getType());
holder.Location.setText(users.getLocation());
}
#Override
public int getItemCount() {
return usersList.size();
}
public class UserHolder extends RecyclerView.ViewHolder{
TextView Name,Type,Location;
public UserHolder(#NonNull View itemView){
super(itemView);
Name=itemView.findViewById(R.id.textTitle);
Type=itemView.findViewById(R.id.textType);
Location=itemView.findViewById(R.id.textLocation);
}
}
}
main activity code
public class MainActivity2 extends AppCompatActivity {
private static final String URL = "http://10.0.2.2/mad/activitydisplay.php";
RecyclerView recyclerView;
UserAdapter userAdapter;
List<Users> usersList;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main2);
recyclerView = findViewById(R.id.recylcerList);
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
usersList=new ArrayList<>();
LoadAllUser();
}
private void LoadAllUser() {
JsonArrayRequest request =new JsonArrayRequest(URL, new Response.Listener<JSONArray>() {
#Override
public void onResponse(JSONArray array) {
for (int i=0;i<array.length();i++){
try {
JSONObject object=array.getJSONObject(i);
String name=object.getString("eventname").trim();
String type=object.getString("type").trim();
String location=object.getString("location").trim();
Users user= new Users();
user.setName(name);
user.setType(type);
user.setLocation(location);
usersList.add(user);
} catch (JSONException e) {
e.printStackTrace();
}
}
userAdapter=new UserAdapter(MainActivity2.this,usersList);
recyclerView.setAdapter(userAdapter);
}
},new Response.ErrorListener(){
#Override
public void onErrorResponse(VolleyError error){
Toast.makeText(MainActivity2.this, error.toString(), Toast.LENGTH_SHORT).show();
}
});
RequestQueue requestQueue=Volley.newRequestQueue(MainActivity2.this);
requestQueue.add((request));
}
}
php code to get data from table
$sql="SELECT * FROM `activitytable` ";
$result=mysqli_query($conn,$sql);
$user=array();
while($row = mysqli_fetch_assoc($result)){
$index['eventname']=$row['eventname'];
$index['type']=$row['type'];
$index['location']=$row['location'];
array_push($user, $index);
}
echo json_encode($user);
activity_main2.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity2">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/recylcerList"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</LinearLayout>
activity_list resource file
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<androidx.cardview.widget.CardView
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="16dp"
android:orientation="vertical">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_vertical"
android:orientation="horizontal" >
<TextView
style="bold"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Title:"
android:textColor="#color/black"
android:textSize="24dp" />
<TextView
android:id="#+id/textTitle"
style="bold"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="#color/black"
android:textSize="24dp" />
</LinearLayout>
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_vertical"
android:orientation="horizontal" >
<TextView
style="bold"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Type:"
android:textColor="#color/black"
android:textSize="24dp" />
<TextView
android:id="#+id/textType"
style="bold"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="#color/black"
android:textSize="24dp" />
</LinearLayout>
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_vertical"
android:orientation="horizontal" >
<TextView
style="bold"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Location:"
android:textColor="#color/black"
android:textSize="24dp" />
<TextView
android:id="#+id/textLocation"
style="bold"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="#color/black"
android:textSize="24dp" />
</LinearLayout>
</LinearLayout>
</androidx.cardview.widget.CardView>
</LinearLayout>

instead of
public UserHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View userLayout= LayoutInflater.from(parent.getContext()).inflate(R.layout.activity_main2,parent,false);
return new UserHolder(userLayout);
}
use this
public UserHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View userLayout= LayoutInflater.from(parent.getContext()).inflate(R.layout.activity_list ,parent,false);
return new UserHolder(userLayout);
}
because activity_main2 doesn't contain R.id.textTitle,R.id.textType,R.id.textLocation

check your xml(R.layout.activity_main2) looks like id of your view are from another layout

OnClickListener in ViewHolder not being entered

I have a recycler view displaying all posts made by a user in my app. I want the users to be able to click on one of the posts and be brought to a new fragment where they can only see the post they have chosen.
When I run my code, and click on one of the posts, the OnCLickListener isn't even triggered.
I have tried adding break points on public void OnClick but it never gets triggered. I have tried adding the OnClick to the onBindViewHolder but I understand this isn't a good idea.
public class PostAdapter extends RecyclerView.Adapter<PostAdapter.PostViewHolder> {
public List<Post> postList;
private Context context;
private static OnItemClickListener onItemClickListener;
public PostAdapter(){
}
public interface OnItemClickListener{
void onItemClick(View v, int position);
}
public void updateList(List<Post> list){
postList = list;
notifyDataSetChanged();
}
public static class PostViewHolder extends RecyclerView.ViewHolder{
TextView postName, postUsername, postDate, postTime, postContent, postId;
PostViewHolder(View v) {
super(v);
this.postName = (TextView) itemView.findViewById(R.id.name);
this.postUsername = (TextView) itemView.findViewById(R.id.username);
this.postDate = (TextView) itemView.findViewById(R.id.date);
this.postTime = (TextView) itemView.findViewById(R.id.time);
this.postContent = (TextView) itemView.findViewById(R.id.content);
this.postId = (TextView) itemView.findViewById(R.id.postId);
v.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
int position = PostViewHolder.super.getAdapterPosition();
onItemClickListener.onItemClick(v, position);
System.out.println("doesn't even make it here");
}
});
}
}
public PostAdapter(List<Post> postList, Context context){
this.postList = postList;
this.context = context;
}
#Override
public PostAdapter.PostViewHolder onCreateViewHolder(ViewGroup parent, int viewType){
View view = LayoutInflater.from(context).inflate(R.layout.all_posts_layout, parent, false);
return new PostAdapter.PostViewHolder(view);
}
#Override
public void onBindViewHolder(PostViewHolder holder, int position){
Post post = postList.get(position);
holder.postUsername.setText(String.valueOf(post.getUsername()));
holder.postName.setText(String.valueOf(post.getName()));
holder.postDate.setText(String.valueOf(post.getDate()));
holder.postTime.setText(String.valueOf(post.getTime()));
}
#Override
public int getItemCount(){
return this.postList.size();
}
Any help would be very much appreciated!
<---card layout for each individual post---->
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="130dp"
android:orientation="vertical">
<ScrollView
android:layout_width="wrap_content"
android:layout_height="130dp">
<android.support.v7.widget.CardView
android:id="#+id/card_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_marginLeft="16dp"
android:layout_marginTop="16dp"
android:layout_marginRight="16dp"
android:layout_marginBottom="2dp"
android:elevation="60dp">
<RelativeLayout
android:id="#+id/search_term_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="1dp">
<TextView
android:id="#+id/name"
android:layout_width="wrap_content"
android:textStyle="bold"
android:layout_height="wrap_content"
android:text="Name"
android:textSize="20sp" />
<TextView
android:id="#+id/username"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textStyle="italic"
android:layout_marginLeft="10dp"
android:layout_toRightOf="#id/name"
android:text="Username"
android:textSize="18sp" />
<TextView
android:id="#+id/date"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/content"
android:layout_alignParentEnd="true"
android:layout_marginEnd="56dp"
android:text="Date"
android:textSize="10sp" />
<TextView
android:id="#+id/time"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="#+id/username"
android:layout_toRightOf="#+id/username"
android:layout_alignParentEnd="true"
android:paddingLeft="8dp"
android:text="Time"
android:textSize="10sp" />
<TextView
android:id="#+id/content"
android:layout_width="315dp"
android:layout_height="48dp"
android:layout_below="#+id/name"
android:layout_alignStart="#+id/name"
android:text="Content"
android:textSize="18sp" />
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/postId"
android:text="ID"
android:layout_below="#id/content"
/>
</RelativeLayout>
</android.support.v7.widget.CardView>
</ScrollView>
</LinearLayout>
<---recycler view to display all posts------>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:tools="http://schemas.android.com/tools">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/filterBtn"
android:text="Filter"
android:background="#drawable/button"
android:layout_margin="2dp"
android:textColor="#color/common_google_signin_btn_text_dark_default"/>
<android.support.v7.widget.RecyclerView
android:id="#+id/update_post_view"
android:layout_width="match_parent"
android:layout_marginTop="50dp"
android:padding="10dp"
android:layout_height="match_parent" />
</RelativeLayout>

Seems like your ScrollView consumes click event. Try to remove it or replace with NestedScrollView

You need to set it in onCreateViewHolder on that view. Also init it in the constructor.

Update code according to this
public static class PostViewHolder extends RecyclerView.ViewHolder, View.OnClickListener {
TextView postName, postUsername, postDate, postTime, postContent, postId;
PostViewHolder(View v) {
super(v);
//init view
v.setOnClickListener(this);
}
#Override
public void onClick(View v) {
onItemClickListener.onItemClick(v, getAdapterPosition());
}
}

**=> You just need to change onBindViewHolder() method code
=> Add click listener on this method.
=> Your code should be like this.**
#Override
public void onBindViewHolder(PostViewHolder holder, int position){
Post post = postList.get(position);
holder.postUsername.setText(String.valueOf(post.getUsername()));
holder.postName.setText(String.valueOf(post.getName()));
holder.postDate.setText(String.valueOf(post.getDate()));
holder.postTime.setText(String.valueOf(post.getTime()));
holder.itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
int position = PostViewHolder.super.getAdapterPosition();
onItemClickListener.onItemClick(v, position);
System.out.println("doesn't even make it here");
}
});
}

unable to make proper ui like playstore

Hi i am developing an app where i have to make a ui like playtstore for that i saw this tutorial but now my problem is that i'm unable to add different
text for different rows and second is that even after setting height and width it doesnt seem to be get affected.
Please if someone can help me out here i'm stuck at this point
my code is as follows
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
int[] images = {R.drawable.vancouver,R.drawable.party,R.drawable.hands_ip,R.drawable.dj};
// Inflate the layout for this fragment
allSampleData = new ArrayList<SectionDataModel>();
createDummyData();
HorizontalAdapter firstAdapter = new HorizontalAdapter(images);
View view = inflater.inflate(R.layout.fragment_home, container, false);
NestedScrollView nestedScrollView = view.findViewById(R.id.scrollView);
llm = new LadderLayoutManager(1.5f, 0.85f, LadderLayoutManager.HORIZONTAL).
setChildDecorateHelper(new LadderLayoutManager
.DefaultChildDecorateHelper(getResources().getDimension(R.dimen.item_max_elevation)));
llm.setChildPeekSize((int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP,
30, getResources().getDisplayMetrics()));
//llm.setReverse(true);
/*llm.setMaxItemLayoutCount(5);
rcv = (RecyclerView) view.findViewById(R.id.rcv);
rcv.setLayoutManager(llm);
new LadderSimpleSnapHelper().attachToRecyclerView(rcv);
adapter = new HSAdapter();
rcv.setAdapter(adapter);
multi_scroll_recyclerview = (RecyclerView)view.findViewById(R.id.multi_scroll_recyclerview);
multi_scroll_recyclerview.setNestedScrollingEnabled(false);
multi_scroll_layout_manager = new LinearLayoutManager(getActivity(),LinearLayoutManager.VERTICAL,false);
multi_scroll_recyclerview.setLayoutManager(multi_scroll_layout_manager);
multi_scroll_adapter = new RecyclerViewDataAdapter(getActivity(),allSampleData);
multi_scroll_recyclerview.setAdapter(multi_scroll_adapter);
multi_scroll_recyclerview.setHasFixedSize(true);*/
/* MultiSnapRecyclerView firstRecyclerView = (MultiSnapRecyclerView)view.findViewById(R.id.first_recycler_view);
LinearLayoutManager firstManager = new LinearLayoutManager(getActivity(), LinearLayoutManager.HORIZONTAL, false);
firstRecyclerView.setLayoutManager(firstManager);
firstRecyclerView.setAdapter(firstAdapter);
HorizontalAdapter secondAdapter = new HorizontalAdapter(images);
MultiSnapRecyclerView secondRecyclerView =(MultiSnapRecyclerView) view.findViewById(R.id.second_recycler_view);
LinearLayoutManager secondManager = new LinearLayoutManager(getActivity(), LinearLayoutManager.HORIZONTAL, false);
secondRecyclerView.setLayoutManager(secondManager);
secondRecyclerView.setAdapter(secondAdapter);
HorizontalAdapter thirdAdapter = new HorizontalAdapter(images);
MultiSnapRecyclerView thirdRecyclerView = (MultiSnapRecyclerView)view.findViewById(R.id.third_recycler_view);
LinearLayoutManager thirdManager = new LinearLayoutManager(getActivity(), LinearLayoutManager.HORIZONTAL, false);
thirdRecyclerView.setLayoutManager(thirdManager);
thirdRecyclerView.setAdapter(thirdAdapter);*/
return view;
}
public void createDummyData() {
for (int i = 1; i <= 5; i++) {
SectionDataModel dm = new SectionDataModel();
dm.setHeaderTitle("Clubs");
dm.setHeadertitle2("Lounge");
dm.setHeadertitle3("Cafe");
dm.setHeadertitle4("Rooftop");
ArrayList<SingleItemModel> singleItem = new ArrayList<SingleItemModel>();
for (int j = 0; j <= 5; j++) {
singleItem.add(new SingleItemModel("Item " + j, "URL " + j));
}
dm.setAllItemsInSection(singleItem);
allSampleData.add(dm);//line which is causing issue
}
}
code for adapter
public class SectionListDataAdapter extends RecyclerView.Adapter<SectionListDataAdapter.SingleItemRowHolder> {
private ArrayList<SingleItemModel> itemsList;
private Context mContext;
public SectionListDataAdapter(Context context, ArrayList<SingleItemModel> itemsList) {
this.itemsList = itemsList;
this.mContext = context;
}
#Override
public SingleItemRowHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
View v = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.list_single_card, null);
SingleItemRowHolder mh = new SingleItemRowHolder(v);
return mh;
}
#Override
public void onBindViewHolder(SingleItemRowHolder holder, int i) {
SingleItemModel singleItem = itemsList.get(i);
holder.tvTitle.setText(singleItem.getName());
/* Glide.with(mContext)
.load(feedItem.getImageURL())
.diskCacheStrategy(DiskCacheStrategy.ALL)
.centerCrop()
.error(R.drawable.bg)
.into(feedListRowHolder.thumbView);*/
}
#Override
public int getItemCount() {
return (null != itemsList ? itemsList.size() : 0);
}
public class SingleItemRowHolder extends RecyclerView.ViewHolder {
protected TextView tvTitle;
protected ImageView itemImage;
public SingleItemRowHolder(View view) {
super(view);
this.tvTitle = (TextView) view.findViewById(R.id.tvTitle);
this.itemImage = (ImageView) view.findViewById(R.id.itemImage);
view.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
//Toast.makeText(v.getContext(), tvTitle.getText(), Toast.LENGTH_SHORT).show();
}
});
}
}
}
My code for model class
public class SectionDataModel {
private String headerTitle,headertitle2,headertitle3,headertitle4;
private ArrayList<SingleItemModel> allItemsInSection;
public SectionDataModel() {
}
public SectionDataModel(String headerTitle, ArrayList<SingleItemModel> allItemsInSection) {
this.headerTitle = headerTitle;
this.allItemsInSection = allItemsInSection;
}
public String getHeaderTitle() {
return headerTitle;
}
public String getHeadertitle2() {
return headertitle2;
}
public String getHeadertitle3() {
return headertitle3;
}
public String getHeadertitle4() {
return headertitle4;
}
public void setHeaderTitle(String headerTitle) {
this.headerTitle = headerTitle;
}
public void setHeadertitle2(String headertitle2) {
this.headertitle2 = headertitle2;
}
public void setHeadertitle3(String headertitle3) {
this.headertitle3 = headertitle3;
}
public void setHeadertitle4(String headertitle4) {
this.headertitle4 = headertitle4;
}
public ArrayList<SingleItemModel> getAllItemsInSection() {
return allItemsInSection;
}
public void setAllItemsInSection(ArrayList<SingleItemModel> allItemsInSection) {
this.allItemsInSection = allItemsInSection;
}
}
listitem.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="?android:selectableItemBackground"
android:orientation="vertical"
android:padding="5dp">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<com.ct.listrtrial.Custom.CustomTextViewMedium
android:id="#+id/itemTitle"
android:layout_width="0dp"
android:layout_weight="8"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_centerVertical="true"
android:layout_gravity="center_vertical"
android:layout_toLeftOf="#+id/btnMore"
android:text="Sample title"
android:textColor="#android:color/white"
android:textSize="27sp" />
<ImageView
android:id="#+id/btnMore"
android:layout_width="0dp"
android:layout_weight="0.8"
android:layout_marginTop="13dp"
android:layout_height="wrap_content"
android:layout_alignParentEnd="true"
android:layout_alignParentRight="true"
android:layout_centerVertical="true"
android:background="#drawable/ic_more_horiz_black_24dp"
android:textColor="#FFF" />
</LinearLayout>
<android.support.v7.widget.RecyclerView
android:id="#+id/recycler_view_list"
android:layout_width="match_parent"
android:layout_marginTop="10dp"
android:layout_height="160dp"
android:layout_gravity="center_vertical"
android:orientation="horizontal" />
</LinearLayout>
main fragment.xml
<android.support.v4.widget.NestedScrollView android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/scrollView"
android:fillViewport="true"
android:background="#color/colorPrimary"
xmlns:android="http://schemas.android.com/apk/res/android">
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<android.support.v7.widget.RecyclerView
android:id="#+id/rcv"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_gravity="center_horizontal"
android:layout_weight="1"
android:paddingBottom="10dp"
android:paddingTop="10dp" />
<android.support.v7.widget.RecyclerView
android:id="#+id/multi_scroll_recyclerview"
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_weight="1">
</android.support.v7.widget.RecyclerView>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
</LinearLayout>
</LinearLayout>
</android.support.v4.widget.NestedScrollView>
listsinglecard.xml
<android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="220dp"
android:layout_marginLeft="18dp"
android:layout_height="200dp"
app:cardCornerRadius="65dp"
>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="?android:selectableItemBackground"
android:orientation="vertical">
<ImageView
android:id="#+id/itemImage"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="center_horizontal"
android:scaleType="centerCrop"
android:src="#drawable/vancouver" />
<TextView
android:id="#+id/tvTitle"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="#id/itemImage"
android:gravity="center"
android:padding="5dp"
android:visibility="gone"
android:text="Sample title"
android:textColor="#android:color/black"
android:textSize="18sp" />
</LinearLayout>
</android.support.v7.widget.CardView>

Recycler View and Card View not displaying cards

This is my Activity:
public String id;
public String passPhrase;
public ArrayList<SongCell> songs;
private RecyclerView recyclerView;
private MyAdapter myAdapter;
private RecyclerView.LayoutManager layoutManager;
#TargetApi(Build.VERSION_CODES.JELLY_BEAN)
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.songs_view_layout);
Context context = this.getApplicationContext();
Bundle stateData = getIntent().getExtras();
try
{
id = stateData.getString("id");
passPhrase = stateData.getString("passPhrase");
ArrayList data;
recyclerView = (RecyclerView) findViewById(R.id.song_list);
recyclerView.setHasFixedSize(true);
layoutManager = new LinearLayoutManager(this);
recyclerView.setLayoutManager(layoutManager);
recyclerView.setItemAnimator(new DefaultItemAnimator());
data = new ArrayList<SongCell>();
for (int i=0; i<5;i++)
{
data.add(new SongCell("Song "+i,"Artist "+i, null));
}
myAdapter = new MyAdapter(data);
recyclerView.setAdapter(myAdapter);
}
catch(Exception e)
{
Log.d("Error: ", e.toString());
}
}
card.xml
<android.support.v7.widget.CardView android:layout_width="fill_parent"
android:layout_height="wrap_content"
xmlns:android="http://schemas.android.com/apk/res/android">
<RelativeLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:padding="6dp"
>
<ImageView
android:layout_width="70dp"
android:layout_height="70dp"
android:id="#+id/song_photo"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_marginRight="16dp"
android:background="#drawable/error" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/song_name"
android:textSize="30sp"
android:text="Song Name"
android:layout_centerVertical="true"
android:layout_centerHorizontal="true"
android:textColor="#000000" />
<ImageButton
android:layout_width="60dp"
android:layout_height="60dp"
android:id="#+id/vote_button"
android:layout_alignParentRight="true"
android:layout_marginRight="8dp"
android:background="#drawable/arrow" />
</RelativeLayout>
</android.support.v7.widget.CardView>
Activity.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent" android:layout_height="match_parent"
android:background="#2d2d2d">
<TableLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<TableRow
android:layout_width="fill_parent"
android:layout_height="match_parent"
android:paddingBottom="30dp"
android:layout_marginBottom="10dp"
android:background="#222222"></TableRow>
<TableRow
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center"
android:paddingBottom="10dp">
<LinearLayout
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center">
<ImageView
android:layout_width="70dp"
android:layout_height="70dp"
android:id="#+id/featSongImage1"
android:contentDescription="#string/newsongimage"
android:background="#drawable/error" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceSmall"
android:text="#string/songname"
android:id="#+id/featSongName1" />
<ImageButton
android:layout_width="25dp"
android:layout_height="25dp"
android:id="#+id/featSongButt1"
android:background="#drawable/arrow"
android:contentDescription="#string/votearrow" />
</LinearLayout>
</TableRow>
<TableRow
android:layout_width="match_parent"
android:layout_height="match_parent"
android:foregroundGravity="fill_horizontal"
android:gravity="fill_horizontal|center">
<android.support.v7.widget.RecyclerView
android:id="#+id/song_list"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_gravity="center_horizontal" />
</TableRow>
</TableLayout>
</LinearLayout>
And this is my custom adapter
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder>
{
private ArrayList<SongCell> data;
public MyAdapter(ArrayList<SongCell> dataI)
{
data = dataI;
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup viewGroup, int viewType)
{
View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.song_card,viewGroup,false);
return new ViewHolder(view);
}
#Override
public void onBindViewHolder(ViewHolder viewholder, int pos) {
viewholder.songName.setText(data.get(pos).getName());
viewholder.artist.setText(data.get(pos).getArtist());
viewholder.image.setImageBitmap(data.get(pos).getArtwork());
}
#Override
public int getItemCount() {
return 0;
}
#Override
public int getItemViewType(int position) {
return 0;
}
public class ViewHolder extends RecyclerView.ViewHolder
{
TextView songName;
TextView artist;
ImageView image;
ImageButton voteButton;
public ViewHolder(View v)
{
super(v);
this.songName = (TextView) v.findViewById(R.id.song_name);
this.image = (ImageView) v.findViewById(R.id.song_photo);
this.voteButton = (ImageButton) v.findViewById(R.id.vote_button);
}
}
}
I have looked at a ton of guides on how to get this working but it still doesn't work. Anyone have any clue what's going on? I'm on version 25.0.1, and have all the modules imported. But it's not adding a single card into the layout.

I thought it would be difficult to debug such a big code you uploaded. But luckily my eye went on this line
#Override
public int getItemCount() {
return 0;
}
return 0; in adapter.
Your list size is always 0.
instead write this
#Override
public int getItemCount() {
return data.size();
}
EDIT-1:
You will also get null pointer exception here
viewholder.artist.setText(data.get(pos).getArtist());
Because you are not initializing the artist variable in ViewHolder class.
Edit-2
#Override
public int getItemCount() {
return 0;
}
you can remove this particular code from your adapter. Because overriding the methods of class that we don't use might sometimes result in errors that you can't even imagine.

Adding Custom Header to List Fragment in Android

I am trying to add a custom header that isnt clickable but will have a checkbox that will "check all" checkboxes under it.
This is my List Fragment
public class AssesmentListFragment extends ListFragment {
private static String BUNDLE_KEY_APPLICATION = "LIST_ITEM";
FastAssesmentListAdapter adapter;
View listHeader;
public AssesmentListFragment() {}
public AssesmentListFragment(Data[] data) {
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Data[] assestments = {new Data("Assesment ID","Name", "Date"), new Data("123456", "Assestment 2", "9/12/12"),
new Data("345672", "Assesment 3", "9/13/12"), new Data("566893", "Assesment 4", "9/14/12")};
//This is the part that makes the app crash
View header = getActivity().getLayoutInflater().inflate(R.layout.list_adapter_assesments, null);
ListView listView = getListView();
listView.addHeaderView(header);
adapter = new FastAssesmentListAdapter(getActivity(), assestments);
setListAdapter(adapter);
updateList(assestments);
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
}
private void updateList(Data[] assestments) {
// NOTE: addAll is not being used to support pre-honeycomb devices
synchronized(adapter) {
adapter.clear();
adapter.addAll(assestments);
adapter.notifyDataSetChanged();
}
}
#Override
public void onListItemClick(ListView parentView, View selectedItemView, int position, long id) {
String model = (String) parentView.getItemAtPosition(position);
((FacilityActivity) getActivity()).onItemSelected(model);
}
#Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
//outState.putInt("curChoice", mCurCheckPosition);
}
}
This is the layout I am trying to use for header
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:paddingLeft="25dp"
android:paddingRight="10dp"
android:orientation="horizontal">
<TextView android:id="#+id/adapter_header_textview_column1"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="4"
android:textColor="#color/defaultTextColor"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textSize="28sp"
android:text="Assesment ID" />
<TextView android:id="#+id/adapter_header_textview_column2"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="4"
android:textColor="#color/defaultTextColor"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textSize="28sp"
android:text="Name" />
<TextView android:id="#+id/adapter_header_textview_column3"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="3"
android:textColor="#color/defaultTextColor"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textSize="28sp"
android:text="Date"/>
<CheckBox
android:id="#+id/header_check_box"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:color="#color/defaultTextColor"
android:layout_weight=".5"
android:gravity="center" />
</LinearLayout>
<View
android:layout_width="fill_parent"
android:layout_height="5dp"
android:background="#color/BPGreenColor" />
<ListView
android:id="#android:id/list"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
</ListView>
</LinearLayout>
Then this is the array adapter I am using:
public class FastAssesmentListAdapter extends ArrayAdapter<Data> {
private static int LAYOUT_ID = R.layout.list_adapter_with_checkbox_three_column;
private final Data[] assesments;
private final Context context;
LinearLayout listHeader;
static class ViewHolder {
protected TextView column1;
protected TextView column2;
protected TextView column3;
protected CheckBox checkbox;
}
public FastAssesmentListAdapter(Context context, Data[] assesments) {
super(context, LAYOUT_ID, assesments);
this.context = context;
this.assesments = assesments;
}
//ListFragment and array adapter will automatically call this over and over to auto populate the list
#Override
public View getView(int position, View convertView, ViewGroup parent) {
final Data item = getItem(position);
// Formulate row view (create if it does not exist yet)
View view = convertView;
if(view == null) {
LayoutInflater inflater = ((Activity) getContext()).getLayoutInflater();
view = inflater.inflate(LAYOUT_ID, null);
final ViewHolder viewHolder = new ViewHolder();
viewHolder.column1 = (TextView) view.findViewById(R.id.adapter_textview_column1);
viewHolder.column2 = (TextView) view.findViewById(R.id.adapter_textview_column2);
viewHolder.column3 = (TextView) view.findViewById(R.id.adapter_textview_column3);
viewHolder.checkbox = (CheckBox) view.findViewById(R.id.check_box);
view.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
Toast.makeText(getContext(), "Clicked",
Toast.LENGTH_SHORT).show();
Intent intent = new Intent(getContext(), FacilityActivity.class);
getContext().startActivity(intent);
}
});
if(viewHolder.checkbox != null) {
viewHolder.checkbox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton buttonView,
boolean isChecked) {
if(isChecked) {
item.setSelected(isChecked);
Toast.makeText(getContext(), "Checked",
Toast.LENGTH_SHORT).show();
}
}
});
}
view.setTag(viewHolder);
viewHolder.checkbox.setTag(position);
}
ViewHolder viewHolder = (ViewHolder) view.getTag();
viewHolder.checkbox.setTag(position);
viewHolder.column1.setText(item.getColumn1());
viewHolder.column2.setText(item.getColumn2());
viewHolder.column3.setText(item.getColumn3());
viewHolder.checkbox.setChecked(item.isSelected());
return view;
}
}
on a side note, the onlistitemclicked in the fragment doesnt work, i have to set a listener in the adapter and then it works. any ideas on that? but mainly I need to figure out how to use a custom header and custom rows in the list view. Here is the layout for the rows
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:paddingLeft="25dp"
android:paddingRight="10dp"
android:orientation="horizontal">
<TextView android:id="#+id/adapter_textview_column1"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="4"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textSize="25sp" />
<TextView android:id="#+id/adapter_textview_column2"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="4"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textSize="25sp" />
<TextView android:id="#+id/adapter_textview_column3"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="3"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textSize="25sp" />
<CheckBox
android:id="#+id/check_box"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight=".5"
android:gravity="center" />
</LinearLayout>